Flue-expander.



' inner bearing surface is UNITED lsTxTEs PATENT OFFICE.

GEORGE B. RICH,

' CHICAGO,

FLUE-EXPANDER.

To all whom it may concern:

Beit knownl that I, GEORGE R. RICH, a citizen of the United States, residing at Oak Park, in the county of Cook and State of Illinois, have invented new and useful Improvements in Flue-Expanders, of which the following is a specification.

'lhis invention relates toy iue expanders of that class employing an expanding member' comprising a plurality of sector-like sections grouped together to form a cylindrical body arranged around a solid tapered core or mandrel. v U

One object of this invention is to avoid certain objectionable features heretofore present in Hue expanders of this class. `1n using the ordinarv flue expanders, much difficu-lty is encountered in maintalning the sector-like sections of the expanding member in alinement the result being that when one of said sections gets out of alinement, itis usually broken in the course of work. Sometimes conical mandrels are'employed in connection with a sectional expanding member, Whose fitted to the mandrel at its smallest end, but it is obvious that when the larger end of the mandrel enters said expanding member 'in the Work of ex panding a flue, the corners of the inner bearing surfaces of `the sectionsare in constant danger of being broken,'because of the difference in radius of the bearing surfaces, l have overcome these objectionablefeatures in the present flue expander which forms the subject matter of the present application.

The invention is clearly illustrated in t-he drawing furnished herewith in which- Figure 1 is a side elevation of one form of my present invention, -the expanding member occupying a position at the small end of the mandrel, Fig. 2 is an end view thereof looking in the direction of the arfrow 2, in Fig. 1, Fig. 3 is a view of the ue expander with the expanding member moved to a position near the middle of the mandrel, the view being. partly in side elevation and partly in longitudinal section, the line of section being indicated at 3-3 in Fig. 4, Fig. 4 is a view partly in end elevation and partly in cross section, the line of section being indicated at 4.-4 Fig. 3, Fig.

5 isan end .vlew of the mandrel looking in the directionof the arrow 2 in Fig. 1, and

Specicaition of Letters Patent. Application mea'october 1e, 1911.' serial Nb; 654,8;1'7.

with the core or mandrel,

Patented Dee. 31, 1912.

Fig. 6 is a perspective view of one of the sector-like sections.

Referring to said drawings A, represents a core or mandrel and B, an expanding member slidably mounted upon said mandrel and capable of being expanded radially thereof by the action of the mandrel thereon. Said member comprises a plurality of sector-like sections 10, freely grouped around its center as shown in Fig. 2, the exterior surface of said expanding member being shaped in conformity with the common practice to suit the work to be done. It is usual to taper one end slightly, as shown, and to provide an annular recessed portion l1, in the face of the expanding member. A central tapered opening 12, in the expanding member receives the tapered core or mandrel, which is forced therethrough in the operation of expanding a iue.

The mandrel and expanding member are provided with co-acting bearing surfaces constructed and arranged. to maintain the several sections of the expanding member in perfect alinement with the mandrel at any working position thereon and the form illustrated in the drawing will now be described.

The mandrel A, is of tapered formation and has a number of 4lon itudinal grooves 13, formed in its face, sai grooves extending from its smaller end to a point near its larger end and being symmetrically disposed around the mandrel; the grooves corresponding in number to the number of sections comprising t-he expanding member. In the form of the invention shown in the drawing, each groove is of curved formation, the radius of the arc of the curve being constant throughout the length of the groove, so that while the arc is of less extent at the smaller end of the mandrel than at the larger end, the same curve is preserved throughout. Each section 10, of the expanding member' B, is formed on its inner side with an outwardly curved bearing face 14, the arc of which has a radius equal to the radius of any of the grooves 13; said bearing face consequently fitting and conformin to any groove in said mandrel at any point in its length. The result is that when the mandrel is forced through the central opening 12, of the expanding member, each section of said member is maintained OF OAK PARK., ILLINOIS, ASSIGNOBTO RICH .TOOL COMPANY, 0F

ILLINOIS, A CORPORATION OF ILLINOIS.

` the corners of the sections 10, or the ridges between the grooves of the mandrel. By reason of the peculiar formation of the grooves in the mandrel and the inner bearingofaces of the freely grouped sector like sections, said sections may rock on the mandrel to accommodate changes in the transverse section of the flue. In Fig. 3 one section 10a, is shown in longitudinal section, for the purpose of illustratin the correct alined position of any section o .the expanding member at any point in the groove.

-To hold the sectionsr of the expanding member together, while permitting them to be moved outwardly radially, by the action of the mandrel, I have provided yielding retaining members, here shown as comprising two split, spring rings 15, 16, that are seated in undercut portions of grooves 17, formed in the end faces of the expanding member. Said rings, by reason of their elasticity, act to hold the several sections together upon the mandrel, and do not interfere with the handling of the expanding member because they are wholly-confined within the grooves.

In operation, the expanding member is inserted in the end of the iiue and the mandrel driven through the central opening thereof, thereby forcing the sections of the expanding member outward radially against the ue, and forcing the flueinto `contact with the flue sheet. The several sections ofthe expanding member remain in perfect alinement with the mandrel by reason of the I realize that various alterations and modlfications of this device are possible without departing from the spirit of my invention, and I do `not therefore desire to limit myself to the exact form of construction shown and described.

I claim as new and desire to secure by Letters Patent:

A flue expander, comprising a tapered solid mandrel whose entire working face is formed with longitudinal grooves paralleling its face, each groove being curved in cross sect-ion and the radius of the curve being constant throughout the length'of the groove, and a substantially cylindrical expanding member comprising sector-like sections freely grouped around the mandrel, each section having an inner, outwardly curved bearing face'of the same radius as any groove on the mandrel, whereby said sections may rock thereon to accommodate changes in the transverse section of the flue.

In witness whereof I have hereunto signed my name at Chicago, Cook county, Illinois,

this 12th day of October 1911.

GEORGE R. RICH.

Witnesses: l

JAS. L. MARQUA, WM. R. MAU. 

